1. Field of the Invention
The present invention relates generally to a head lamp for a cornering operation to be performed by a vehicle, especially a motorcycle motorcycle. More particularly, the present invention relates to a so-called cornering head lamp which is constructed to correct variation of the property of light orientation induced by inclination of a vehicle body of the motorcycle during a cornering operation on the road surface.
2. Description of the Related Art
To facilitate understanding of the present invention, a typical conventional cornering head lamp will briefly be described with reference to FIG. 9. In the drawing, the cornering head lamp is generally designated by reference numeral 31. A vehicle body 20 of the motorcycle is equipped with an inclination sensor 21 adapted to be operated by using a supersonic. The head lamp 31 is turnably supported on the vehicle body 20 to turn about an optical axis such that it is turned relative to the ground surface 22 in response to an output from the inclination sensor 21. Specifically, when the vehicle body 20 is inclined as shown in the drawing during a cornering operation and this inclined state is detected by the inclination sensor 22, the head lamp 31 is turnably driven relative to the ground surface 22 by driving means 23, e.g., a motor. An extent of turning movement of the head lamp 31 about the optical axis is determined such that the property of light orientation becomes parallel to the ground surface 22, i.e., assumes the same state as that at the time when the vehicle body 20 stands upright on the ground surface 22. This makes it possible to obviate such a problem that light fails to be correctly irradiated from the head lamp 31 in the forward direction of the motorcycle.
However, since the conventional head lamp 31 is constructed such that the whole head lamp 31 is turned with a large magnitude of load imposed on the driving means 23, it is unavoidable that the head lamp 31 is designed in larger dimensions. This leads to an inconsistent problem that in spite of the requirement for mounting the cornering head lamp on the vehicle body of the motorcycle in view of inclination of the vehicle body during a cornering operation, the head lamp 31 is mounted on a small-sized vehicle, e.g., a motorcycle with much difficulties.